现代电信网运行维护的技术支持系统

在电信网达到一定规模，网路建设速度放慢之时，在设备 应商的名费技术支持到期后，数千万端口多种型号的交换设备和大量传输设备的技术支持由谁来承担？中国电信将采用什么策略 技术手段来保障维护部门能及时得到优质高效的技术支持？本文作者长期从事本地网网管和集中监控系统的开发和工程实施，深深感到与网管配套的运行维护技术支持系统在电信支撑网的建设中的重要性。     

Digital Switching in France

This paper intends firstly to present how digital switching was introduced into the French network nearly ten years ago and what are the main advantages brought by digital switching systems. Various cases in the network such as trunk or local exchanges are examined; general as well as particular advantages are shown. Secondly, the technical requirements for these exchanges are described; an emphasis is put on the specific aspects of digital switching. Digital switching systems already in operation or on the verge of being commissioned are outlined. Finally, different tables give information concerning mainly the number of subscriber lines connected to class 3 and 4 digital exchanges by the end of 1978.     

构建ADSL宽带数据网络综合运营维护系统

分析了目前ADSL宽带数据网络运营维护所面临的问题，提出了构建ADSL宽带数据网络综合运营维护系统的解决方案。     

Operation and maintenance field experience for off‐grid residential photovoltaic systems

The field performance of photovoltaic systems has been studied extensively for many applications and a number of databases exist in the United States and internationally. However, these databases focus almost exclusively on the system elecrical performance. Published information on the operation and maintenance (O&M) experience and costs for photovoltaic systems is almost nonexistent. At a time when photovoltaics is being considered as a viable option for distributed energy generation, it is critical that maintenance experience be captured to identify lifecycle costs and/or levelized energy costs for these systems, as well as to identify areas for system and component improvements. This paper addresses the data collection, analysis and results of an off‐grid residential customer service program offered by the Arizona Public Service (APS) Company over a six‐year period from 1997 through 2002. Standardized, packaged photovoltaic systems were offered and operated by APS through a lease arrangement with customers throughout the state of Arizona. The operation and maintenance records for these systems were carefully tracked and analyzed. The O&M costs, database development, cost drivers, lifecycle cost implications, and lessons learned are presented and discussed. Copyright © 2004 John Wiley & Sons, Ltd.     

面向NGN的运营支撑系统

传统电信网以网络运行维护为中心，而下一代网络（NGN）是以分组交换为主的网络，采用开放的网络架构体系，其运营支撑以客户为中心。立足于在NGN运营维护系统建设上以客户为中心，以市场为导向，以效益为目标，中出通讯在NGN网络上实现了完整的覆盖各个功能层次的网管系统，并且建设在统一的运营支撑维护系统平台之上，能够灵活地进行技术升级以适应技术演进的需要，为运营商提供了新的面向客户的服务。     

Public telecoms networks. Is the UK on the right line?

The introduction of digital telephone exchanges, among other factors, is causing telephone operators worldwide to set their standards for the new systems. The UK is following a slightly different path from most other countries. The main differences cover equipment specification and approval, and the installation, operation and maintenance of new equipment. British Telecom has opted for a strategy based largely on the hierarchical technique-a separate digital overlay network of 53 main switching networks interlinked by CCITT Number 7 signalling. The author discusses how this differs from the digital-island technique used in other countries. The UK regulatory situation, standards and administration practices are also discussed     

交换机实时监控设备方案设计

针对当前市场上的主流交换机,提出了交换机实时监控系统设计方案,力求为用户提供更为完善、可靠的交换机系统,大幅度提高交换机维护效率,并减轻机房工作人员维护负担。方案根据现有交换机条件和系统性能要求,提出了基于实时操作系统(RTOS)和基于裸处理器的开发思路,详细地阐述了每种情况所需要的关键技术和开发人员应具备的理论知识,同时还提出了电子显示布告牌设计中需考虑的核心问题。     

动力设备和环境集中监控系统的应用

基站动力设备及环境集中监控系统在移动公司的运营维护中已发挥了不可替代的作用，本文通过对基站动力设备和环境集中监控系统应用实例的研究分析，着重探讨如何充分发挥监控系统的作用，为移动通信网络新的运营维护管理模式提供科学理论依据。     

MSTP的应用与发展

多业务传送平台(MSTP)和数据设备的关系是联合组网、长期并存的关系,运营商的运维体制必须改革,不能仍将传输设备和数据设备截然分开进行建设;互连互通涉及到业务层、封装层、数据处理层、SDH承载层、SDH线路侧,运营商应重点关注;MSTP的进一步发展是加载自动交换光网络(ASON)控制平面,但要注意在支持数据业务的情况下,传送平面和控制平面在带宽调整方面的协调性;MSTP将来可能有两种转向:逐步退出传送网络的核心层或演化成为事实上的以分组交换为核心的承载网设备.     

5G核心网云网一体化运维

全球大多数主流运营商已转向5G独立组网架构,并开始了5G独立组网架构的商用部署。5G核心网采用网络功能虚拟化技术,将通用的计算、存储、网络等硬件形成多种虚拟资源,基于需要实现网络功能及资源动态灵活性部署。随着网络功能虚拟化的5G核心网的大规模商用部署,5G核心网的运营维护也面临新的挑战。分析了5G核心网的虚拟化部署方案带来的运营维护工作难点,提出5G核心网运营维护系统建设的架构和方案,并在此基础上提出5G核心网云网一体化运营维护组织架构建议,为5G核心网云网一体化运维工作提供参考。     

OA&M framework for multiwavelength photonic transport networks

Photonic networks based on wavelength division multiplexing (WDM) and optical path technologies are expected to realize flexible, transparent, and cost-effective transport networks with a large transmission capacity. This paper explores the design framework of photonic transport networks taking into consideration the operation administration and maintenance (OA&M) functions required for the successful introduction of WDM systems based on the optical path concept. From the view point of network maintenance, clear distinction is made between the optical path layer and the optical section layer to facilitate accurate and smooth failure localization. The digital multiplexing span between physical multiplexing interfaces at the end-to-end digital nodes should have the same maintenance span as the corresponding optical path. We argue that cooperative maintenance by OA&M functions at both the digital and optical layers can be a practical way of network supervision. A supervisory (SV) signal transfer method and a configuration that is suitable for the terrestrial trunk network are also indicated. As an example, a practical SV system design methodology and an actual procedure developed for a single channel optical transmission system based on optical in-line amplifiers are introduced. Furthermore, application of the developed SV system and network restoration schemes is discussed for future WDM-based photonic networks. The OA&M aspects introduced will be valuable for creating future photonic network systems     

话务统计分析在运行维护和市场营销中起的作用

通过对C&C08交换系统话务统计功能的实际应用,说明了应用方法以及对运行维护工作和市场营销工作的指导作用,也阐述了做好话务统计分析对通信运营商的重要性。     

Maintenance strategies for PCM circuit switching

During all the system design phase of an SPC switching system, a considerable effort is devoted to maintenance, both from a hardware and software point of view. The maintenance phases include fault detection, fault analysis (e.g., identification of the faulty security block within the switching system), fault isolation, fault reporting, fault localization, fault clearance, and restoration to service with the eventual requalification and reinitialization of the repaired security block. The paper mainly discusses fault detection and fault analysis strategies with specific reference to PCM digital switching systems. Different means leading to fault detection are presented with reference to central control, network access devices (scanners, drivers, markers), and digital switching network (duplicated or not duplicated). These means include automatic on-line tests (monitoring and routining), on-demand on-line tests, and alarm handling. Fault analysis can be accomplished by means of a deductive or a statistical method. As the latter seems more attractive, three basic methods of statistical fault analysis are presented. They use, respectively, two counters (operation and fault counter) per security block; one fault counter per security block; one "historical" fault stack, in which all the identities of security blocks involved in faulty operations are stored. The above fault analysis strategies are compared mainly in terms of core memory occupancy, processor time, and software complexity.     

Design of a Switched Broad-Band Communications Network for Interactive Services

The congestion in broad-band communications networks resulting from the increased demand for interactive services is considered. It is shown that services such as a video library could not be provided to the majority of subscribers in a conventional CATV network. A design is developed for a space division multiplex broad-band network which can be expanded at minimum cost to meet an increasing demand for interactive services. The network contains two signal distribution networks: a cablecast system similar to the Rediffusion system, and a switched communication network providing point-to-point circuits for both one-way and two-way services. All broad-band signals are transmitted to the subscribers in the 1- to 10-MHz spectrum, permitting the use of twisted pair video cables and a minimum number of cable amplifiers. The broad-band cable network (BCN) is organized around 15 local switching exchanges and one central exchange. Multipoint switches in local exchanges under wired-logic circuit control connect individual subscriber communication lines to any channel. Crosspoint matrix switching groups in the local and central exchanges connect communication circuits in the broad-band communication network under programmed computer control. This network is accessed via links terminating on one channel of the multiposition switches. Per-subscriber costs are estimated to be 190 dollars for a cablecast system serving 3800 subscribers. Additional expenditures per subscriber of 40 dollars for fixed costs and 40 dollars for variable costs would provide interactive services. The range of interactive services provided would be extremely flexible, including both one-way video library service and point-to-point two-way communications.     

基于数据分析的网络健康评估系统

云数据中心网络具备复杂性和规模性特征,给网络的运营和维护带来挑战。基于数据分析的网络健康评估系统能够通过数据采集、网络建模、数据分析和综合评估等技术实现网络运行状态量化和可视化,便于网络整体质量动态掌握和故障快速处理,实现网络故障事后发现向事前预测的转变,为网络管理人员提供了网络运营和管理的有效手段,以提升网络运维效率、提高网络运营质量。首先对网络评估系统关键技术进行了介绍,其次结合实践情况给出了基于数据分析的网络健康评估系统的试验效果,最后对该系统功能的进一步完善提出了展望。     

An Experimental Local PCM-Switching System

This paper discusses a local PCM switching network. The characteristics of this network are demonstrated with a model of three local exchanges. All subscribers are connected with the exchange via concentrators. An exchange is controlled by a central processor with a stored program. This processor interacts with the peripheral switching units, represented by the central switching network and two types of control circuits, located within the exchange. These control circuits control either the concentrators or they communicate with counterparts, situated in other local exchanges. All control functions that are not executed by programs of the central processor are realized by microprograms in a wired read-only storage (ROS) in these peripheral control circuits.     

OAM MIB: an end-to-end performance management solution for ATM

Current network management needs an end-to-end overview of various connections rather than the information that is purely local to the individual devices. The typical manager-centric polling approach, however, is not adequate to understand network-wide behavior of a large-scale broadband network. We propose a new management information base (MIB) approach, called operation, administration, and maintenance (OAM) MIB. The MIB provides a network manager with dynamic end-to-end management information by utilizing special standard ATM cells. The MIB makes end-to-end management feasible while it reduces management-related traffic and manager-to-manager interactions. In our model, a customer network management system accesses the MIB through M1/M2 reference points of the ATM Forum management architecture with simple network management protocol (SNMP)     

交换式网络中监听技术的原理及实现

在网络中进行监听是维护、管理网络必须进行的操作。现如今,很多的局域网都已经换成了交换式网络,由于Sniffer监听的原理限制,在交换式网络中不能实现监听。论文详细阐述了网络监听的原理,在交换式网络中实现网络监听的技术和应用,并检测和防范网络中存在的监听。     

An architecture for IP over WDM using time-division switching

This paper proposes an architecture for routing Internet protocol (IP) packets directly on optical networks. The use of label switching is assumed in the IP routers, while a new routing architecture is introduced to transport IP packets across an optical backbone network. The architecture is based on a two-tier multiplexing approach with wavelength division multiplexing (WDM) addressing the number of regional exchanges and time-division switching communicating among the hubs. Such an architecture not only has the advantages of simple network management and high efficiency with low latency; it also is scalable by addition of regional exchanges, hubs, and fibers     

ISDN Activities in Italy

Digitalization of the Italian telecommunications network is underway, as in many other countries, and a significant diffusion of digital transmission has already been achieved. Digital switching has already been introduced at both transit and local levels, with some 450 exchanges presently in operation. Both packet- and circuit-switched data networks are in operation. CCITT No. 7 is presently being introduced. In this network scenario, the already planned Italian developments towards the ISDN will include the provision in 1986 of 64 kbit/s digital connectivity and, two years later, the activation of a pilot ISDN service, whose main characteristics are described in the paper. An overview on further developments in ISDN research areas is also given.